Plate Fin and Tube Heat Exchanger Modeling: Effects of Performance Parameters for Turbulent Flow Regime

Abstract

In the current study, the air-side turbulent thermal and hydraulic characteristics of finned tube heat exchanger of staggered tube arrangement are simulated with steadystate solvers using ANSYS CFX12.0, a Commercial CFD code for turbulent flow regimes. The k-ω model was used to predict the turbulent flow characteristics through the finned tube heat exchanger. The level of confidence of this numerical model was based on a comparison with previous experimental data from the literature, comparing the friction factor f and Colburn factor j, and reasonable agreement is found between the simulations and experimental data. Detailed analysis of the effect of thermal and hydraulic performance of related parameters such as longitudinal pitch, transverse pitch, and fin pitch are also critically evaluated for turbulent flow regime. The increase in the longitudinal pitch and transverse pitch causes a decrease in the heat transfer and pressure drop performance as the flow becomes free and less compact with the increase in the tube pitch. The effect of fin pitch on the heat exchanger performance demonstrates that a decrease in the fin pitch shows the opposite performance to that of the longitudinal and transverse pitches.

Effects of Geometric Parameters for Wavy Finned-Tube Heat Exchanger in Turbulent Flow: A CFD Modeling

“…Also a number of numerical attempts have been accomplished in 2D/3D analysis (Jang and Chen 1997, Bhuiyan, Zaman et al 2010, Bhuiyan, Islam et al 2011, Glazar, Trp et al 2012, Gong, Min et al 2013, Bhuiyan, Amin et al 2014, Lin, Wang et al 2014. But most of the earlier works are limited to laminar to transitional ranges (Chu, He et al 2009, Bhuiyan, Zaman et al 2010, Bhuiyan, Islam et al 2011, He, Chu et al 2013, Bhuiyan, Amin et al 2014. In this study, simulation results for wavy fin considering different tube arrangements for turbulent flow range will be investigated.…”

“…In last decades, several efforts have been devoted to investigate the fundamentals and performance related issues in different experimental works (Kim, Youn et al 1996, Wang, Fu et al 1997, Wang 1999, Yan and Sheen 2000, Wang, Hwang et al 2002, Pirompugd, Wongwises et al 2006, Junqi, Jiangping et al 2007, Kim, Ham et al 2008, Wang, Liaw et al 2011, Dong, Chen et al 2012, Dong, Su et al 2013, Du, Feng et al 2013, Wu, Wu et al 2014. Also a number of numerical attempts have been accomplished in 2D/3D analysis (Jang and Chen 1997, Bhuiyan, Zaman et al 2010, Bhuiyan, Islam et al 2011, Glazar, Trp et al 2012, Gong, Min et al 2013, Bhuiyan, Amin et al 2014, Lin, Wang et al 2014. But most of the earlier works are limited to laminar to transitional ranges (Chu, He et al 2009, Bhuiyan, Zaman et al 2010, Bhuiyan, Islam et al 2011, He, Chu et al 2013, Bhuiyan, Amin et al 2014.…”

Thermal and Hydraulic Performance of Finned Tube Heat Exchangers

“…In the staggered tube arrangement, however, the flow circulates around each downstream tube. The heat transfer and friction factor for both the inline and staggered tube arrangements are affected by various geometrical parameters such as fin pitch, tube pitch, tube diameter and the number of tube rows [1][2][3][4][5]. The successive accelerating and decelerating regions along with the adverse pressure gradient can produce a three-dimensional vortical structure known as a horseshoe vortex system.…”

“…There have been extensive studies on the thermo-hydraulic characteristics of fully ducted fin and tube heat exchangers with a staggered tube configuration, but far less for the inline tube configuration. Most of the early work was experimental [1][2][3][4][5][6][7][8][9], but lately, there have been an increasing number of numerical studies [10][11][12][13]. McQuiston and Tree [7] was one of the first to experiment on two test samples with a fin pitch of 0.173 and 0.3 diameters with an outer tube diameter of 10.3 mm and an inlet velocity ranging from 0.5-5.9 m/s.…”

“…They also found out that the heat transfer coefficient and the friction factor for staggered tube arrangement is 15-27 percent and 20-25 percent, respectively, higher than for the inline tube arrangement. Bhuiyan [1,2] conducted numerical studies of inline and staggered tube geometries with tube pitch less than 2.5 diameters and fin pitch less than 0.4 diameters. The results showed a 25-30 percent higher heat transfer coefficient for the staggered tube arrangement than the inline case but with more than a 40 percent higher friction factor.…”